#include<stdio.h>
#include<assert.h>
char* my_strcat(char *dest , char *scr )
{
    char* ret=dest;
    assert(dest&&scr);
    
    while(*dest)
        dest++;
    while(*scr!='\0')
    {
        *dest=*scr;
        dest++;
        scr++;
    }
    *dest=*scr;
    return ret;
}
int main()
{
    char arr1[20]="abc";
    char arr2[]="bcd";
    my_strcat(arr1,arr2);
    printf("arr1=%s\n",arr1);
    return 0;
}